Aufforth, R., Jain, J., Morreale, J., Baumgarten, R., Falk, J., & Wesen, C. (2012). Paravertebral blocks in breast cancer surgery: Is there a difference in postoperative pain, nausea, and vomiting? Annals of Surgical Oncology, 19(2), 548–552.

To evaluate the effect of paravertebral blocks on the postoperative pain, nausea, and vomiting of patients undergoing breast cancer surgery with or without axillary staging

Chart review

• The sample was composed of 337 patients.   
• Mean patient age was 59.5 years.
• All patients were female.
• All patients underwent breast cancer surgery and received paravertebral blocks (PVBs). Of all patients, 45.5% (110 patients) had mastectomy; in addition, 13.4% (45 patients) had tissue-expander reconstruction, 53.3% (129 patients) had a sentinel lymph node biopsy, and 33.5% (81 patients) had full axillary dissections.  
• A study was excluded if patients had myocutaneous tissue-flap breast reconstruction simultaneous to mastectomy, had additional surgeries, used continuously delivered postoperative pain medication, had a history of chronic pain, or had a history of needing antiemetics prior to surgery.

• Single site
• Inpatient
• Hospital
   

• Phase of care: active treatment
• Clinical applications: late effects and survivorship

Retrospective chart review

• Scores, 0–10, to measure pain
• Opioid analgesic converter as presented on globalRPh.com

In patients who had undergone breast cancer surgery, PVB had no effect on postoperative pain, nausea, or vomiting.

• The pain, nausea, and vomiting scores of patients who had undergone breast cancer surgery with PVBs were similar to the scores of patients who had undergone breast cancer surgery without PVBs.
• The study demonstrated that PVBs can be easily and safely administered. This study did not show any advantage to doing so.

• The study had a risk of bias due to no appropriate control group.
• The list that follows showed other study limitations.
  • The study was retrospective.
  • Not all charts contained consistently recorded postoperative pain scores; the timing or frequency of pain scores varied greatly.
  • Determining the relationship of pain score to administration of pain medication was difficult.
  • Some pain scores were gathered before administration of pain medication; some, after administration.
  • The study lacked a standard postoperative pain medication regimen.
  • Patients received different types of opioids.
  • Some patients received postoperative NSAIDs. Authors did not consider the effect of the NSAIDs on pain.
  • The study had no means of evaluating whether PVBs were successful in reducing pain.
  • Each cohort included significantly different types of breast and axillary surgeries.
     

This study indicated that PVB might decrease postoperative pain in breast cancer surgery patients with immediate breast reconstruction with tissue expanders. PVB may have an important role in decreasing postoperative pain and opioid analgesic usage in patients electing to have immediate breast reconstruction with tissue expanders.